VirtualBox (Virtual Machines, VMs)

see also: VirtualBox 🇩🇪

chattr -R +C ./VirtualBox VMs/

• Sysinternals'sdelete -z C:
• VBoxManage modifyhd somedisk.vdi –compact
  • if error "cannot register the hard disk … because a hard disk … with UUID … already exists":
    VBoxManage modifymedium disk {938781e0-65f5-46de-a656-8118cf761cdb} –compact

.vbox File in the VM folder in VirtualBox VMs could be empty or inaccessible, maybe rename .vbox-prev file to .vbox to fix.